Electronic discovery (also ediscovery or e-discovery) refers to discovery in legal proceedings such as litigation, government investigations, or Freedom of Information Act requests, where the information sought is in electronic format (often referred to as electronically stored information or ESI). Electronic discovery is subject to rules of civil procedure and agreed-upon processes, often involving review for privilege and relevance before data are turned over to the requesting party. Electronic information is considered different from paper information because of its intangible form, volume, transience and persistence. Electronic information is usually accompanied by metadata that is not found in paper documents and that can play an important part as evidence (e.g. the date and time a document was written could be useful in a copyright case). The preservation of metadata from electronic documents creates special challenges to prevent spoliation. In the United States, at the federal level, electronic discovery is governed by common law, case law and specific statutes, but primarily by the Federal Rules of Civil Procedure (FRCP), including amendments effective December 1, 2006, and December 1, 2015. In addition, state law and regulatory agencies increasingly also address issues relating to electronic discovery. In England and Wales, Part 31 of the Civil Procedure Rules and Practice Direction 31B on Disclosure of Electronic Documents apply. Other jurisdictions around the world also have rules relating to electronic discovery. Stages of process The Electronic Discovery Reference Model (EDRM) is an ubiquitous diagram that represents a conceptual view of these stages involved in the ediscovery process. Identification The identification phase is when potentially responsive documents are identified for further analysis and review. In the United States, in Zubulake v. UBS Warburg, Hon. Shira Scheindlin ruled that failure to issue a written legal hold notice whenever litigation is reasonably anticipated will be deemed grossly negligent. This holding brought additional focus to the concepts of legal holds, eDiscovery, and electronic preservation. Custodians who are in possession of potentially relevant information or documents are identified. To ensure a complete identification of data sources, data mapping techniques are often employed. Since the scope of data can be overwhelming or uncertain in this phase, attempts are made to reasonably reduce the overall scope during this phase - such as limiting the identification of documents to a certain date range or custodians. Preservation A duty to preserve begins upon the reasonable anticipation of litigation. During preservation, data identified as potentially relevant